Mayo researchers identify possible way to turn cancerous cells back into healthy cells

Charlie Patton

Monday

Aug 24, 2015 at 1:26 PM

Researchers at the Mayo Clinic in Jacksonville have discovered a possible way to transform cancerous cells back into normal, healthy cells.

Although this "unexpected new biology that provides the code, the software for turning off cancer" is far from ready for use in treating people with cancer, that eventual possibility is very real, said Panos Anastasiadis, Ph.D., Mayo's chair of the Department of Cancer Biology in Jacksonville.

The results of the study, for which Antonis Kourtidis, a research associate in Anastasiadis' lab, was lead author, were published Monday in the journal Nature Cell Biology.

What led to the breakthrough was the discovery that adhesion proteins - the glue that keeps cells together - are involved in the production of molecules called microRNAs. The investigators found that when normal cells come into contact with each other, a specific subset of microRNAs suppresses genes that promote cell growth. However, when adhesion is disrupted in cancer cells, cells grow out of control. The investigators found, in laboratory experiments, that restoring the normal microRNA levels in cancer cells can reverse that aberrant cell growth.

The adhesion proteins E-cadherin and p120 catenins have long been considered to be tumor suppressors. But both Mayo researchers and other studies had found that those proteins are still present in tumor cells, Anastasiadis says.

"That led us to be believe that these molecules have two faces - a good one, maintaining the normal behavior of the cells, and a bad one that drives tumorigenesis," he said.

That led to the search for a different factor that was responsible for good cells going bad. Eventually they pinpointed the problem, a protein called PLEKHA7, which was present in healthy cells, but was absent in cancerous cells.

The loss of PLEKHA7 protein "is an early and somewhat universal event in cancer," Anastasiadis said. "... This produces the equivalent of a speeding car that has a lot of gas but no brakes."

Having identified the absence of the PLEKHA7 protein as a key factor in turning healthy cells into cancerous cells, the next step is to study ways in which the protein might be used to turns cancerous back into healthy cells. That will involve a lot more work, with initial studies performed on animals. Among the cancers they will be studying is bladder cancer. Finding an effective treatment for bladder cancer would be a personal goal for Anastasiadis, whose father died of the disease.

"Maybe years down the road this can make difference for someone with bladder cancer," he said. "That would be nice."